WASHINGTON — The Pentagon has begun paying modest stipends to the Syrian moderates it hopes to field in the fight against Islamic State militants, the military confirmed Monday.

Training of the first group of about 90 fighters began last month. They will be paid stipends of $250 to $400 per month, depending on their skills, performance and leadership, said Navy Cmdr. Elissa Smith, a Pentagon spokeswoman. Preparing the recruits for battle is expected to take several months.

The Pentagon expects to have 3,000 fighters trained by year's end, Smith said. The goal for 12 months is 5,400. She declined to say how many are currently being trained.

"For operational security, we will not announce when coalition-trained Syrian opposition forces enter into Syria," she said.

The training program — branded "critical" by Defense Secretary Ashton Carter — was delayed by several months because finding and vetting fighters who will adhere to laws of war and pledge to conduct themselves properly has proved difficult. Training is taking place in countries that neighbor Syria, including Jordan.

About 6,000 Syrians have volunteered for the training program, more than 4,000 of them awaiting to be vetted, Smith said. Recruiting continues.

The effort to field competent, trained forces in Iraq to battle militants from the Islamic State, known as ISIL and ISIS, has also been slow. ISIL swept through northern Iraq and large portions of eastern Syria last summer, seizing key cities. Iraqi forces have succeeded in taking back some of them, including Tikrit, but were chased without a fight from Ramadi last month.

The Pentagon had hoped to field 24,000 new Iraqi security forces by fall, Carter told Congress last week. But will fall short of that mark because 9,000 had signed up to train.

The Syrian moderates will be equipped with small arms and trained to maneuver and communicate. Their primary mission will be to protect their towns and villages from ISIL fighters. Eventually, they are also envisioned to become a viable opposition to the regime of President Bashar Assad. Civil war has shattered the country, killing 220,000 people and forcing millions from their homes.

Carter also acknowledged last week that the effort to field thousands of trained Syrian moderates has gone slower than expected.

"Our train-and-equip mission in Syria has been challenging," he said. "But the requirement for a capable and motivated counter-ISIL ground force there also means we must persist in our efforts."

Even a small force, if well trained, could make a difference in Syria, said David Phillips, director of the Peace-Building and Rights Program at Columbia University.

"They're not fighting a large army," Phillips said. "Even small numbers can be effective on the battlefield. Nobody envisions this to be an easy or quick win. Developing a nucleus of capable fighters is the right way to start."